1. Field of the Invention
The present invention relates to an iron head of a golf club, especially to a composite material integrally forged iron head of a golf club.
2. Description of Related Art
A conventional iron golf club head is mostly manufactured by forging or casting with one single steel material. Because the material properties lack diversity, the strike performance of the iron golf club head is limited. Therefore, to enhance the strike performance, the iron golf club head must be lightweight and large in volume, so a weight part is installed in the iron golf club head to adjust the density and to increase the properties of the iron golf club head.
The conventional iron golf club heads has several types as follows:
1. Integrated Forged or Cast Iron Head
The materials of the iron golf club head include carbon steel, stainless steel or titanium, which are applied in an integrated forging or casting process. The density of the carbon steel is around 7.7 g/cc to 7.9 g/cc, and the density of the stainless steel is around 7.6 g/cc to 7.8 g/cc. The densities of both of the steel materials are heavy such that it is hard to reduce the weight and increase the volume of the iron golf club head in manufacture. The titanium material can be made of a large-volume iron golf club head, and the density of the titanium material is around 4.5 g/cc. However, the material and manufacturing of a titanium iron golf club head costs too high and can hardly gain the market acceptance.
2. Composite Aluminum Alloy Material Forged Iron Head
The aluminum composite iron golf club head includes a head body and a weight part. The head body is made of carbon steel or stainless steel and is combined with the weight part made of aluminum alloy by forging. The aluminum alloy material has a density of around 2.5 g/cc and has a suitable weight as an ideal material for producing the iron golf club head. In a forging process, the forging temperature is usually from 700 to 1200° C. and the melting point of the aluminum alloy material is only from 650 to 680° C., so the structure of the weight part will be damaged and will not be combined with the head body tightly by forging. The strike performance of the golf iron head is also influenced by the manufacturing process.
3. Composite Titanium Alloy Material Forged Iron Head
The titanium composite iron golf club head includes a head body and a weight part. The head body is made of carbon steel or stainless steel and is combined with the weight part made of titanium alloy by forging. The weight part has a density of around 4.5 g/cc of with good physical properties, but titanium alloy costs higher than other materials and the manufacturing process is complicated, making the price of the iron head product beyond market acceptance. Also, the density of the titanium alloy is slightly less than the density of carbon steel or stainless steel, and thus the weight of the iron golf club head cannot be decreased and the volume of the iron golf club head cannot be increased substantially.
To overcome the shortcomings of the conventional manufacture method, the present invention provides a manufacturing method of an iron golf club head to mitigate or obviate the aforementioned problems.